This NSA glossary from November 2010 provides supporting evidence for the existence of “dictionary based text keywork scanning engines”: see the Intercept article GCHQ and Me: My Life Unmasking British Eavesdroppers, 3 August 2015.

﻿This field is searchable for MB information only, although it is retrievable (in both views) for FARNDALE anc RECOVERY information as well.
The file type as defined in headers of intercept.
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